The inexact science of raising kids | A blog by ScienceNews

Many babies are crummy sleepers, confirming what millions of parents already know

Laura Sanders

8:00am, December 12, 2018

GO TO SLEEP Lots of babies don’t sleep a six-hour stretch at night, even by age 1, a new survey confirms.

Orbon Alija/istock.com

I love to hate the phrase “sleep like a baby.” It’s a beautiful example of a saying that’s based on the exact opposite of what it’s intended to convey. Babies (many of them, anyway) are rotten sleepers.

During my last pregnancy, I wondered if I might luck out with a good sleeper. Or at least an average sleeper. But my third little sweetie didn’t deliver. At nearly 8 months, he (and I) still wake up several times a night. That’s a drag, but not a surprising or big one. This time around, I had very low expectations.

A recent survey of 388 Canadian mothers supports those rock-bottom expectations. It found that many babies don’t sleep through the night. At 6 months of age, 43 percent of infants were sleeping an uninterrupted 8 hours during the night. That means that 57 percent of these babies — more than half — were not. When researchers relaxed their “overnight” definition to mean 6 hours of blissful slumber, 62.4 percent of babies hit the mark; 37.6 percent did not. That’s 1 in 3 babies not sleeping 6 hours at a go — a large chunk of the infant population.

The researchers found some differences among the sleepers and nonsleepers. Breastfed babies were much less likely to sleep in long, solid blocks than formula-fed babies. And baby boys seemed to be slightly worse sleepers than baby girls, with fewer sleeping 6 hours or more at a stretch at age 6 months.

The results raise a question: Are all of those night wakings bad for the baby or the mother? Follow-up tests didn’t find any ill effects, the researchers report. Sleepers and nonsleepers performed similarly on mental and physical tests. And moms of sleepers and nonsleepers scored similarly on mood tests.

The study has all sorts of caveats, one of which is that the mothers were asked to report their baby’s sleep patterns. I know firsthand how unreliable I am on that. I can easily answer the question that greets every parent of a baby: “Does he sleep?” But I can’t necessarily tell you how bad it really is. It’s a dark, shuffling blur.

It’s comforting to know that my babies aren’t the only ones that may force people to retire the “sleep like a baby” description. But another saying remains true and fits this phase of parenthood perfectly: “It goes so fast.” These sleepless nights with a baby in my arms will soon be gone. For now, I’ll enjoy all the snuggles as much as I can.

When it comes to raising kids, good advice and strong evidence can be hard to come by. The Growth Curve blog brings an accessible and metered approach to new studies and popular parenting topics. Growth Curve is a blog of Science News, which gives readers a concise overview of the most important science news from all fields and applications of science and technology.